Website/Forum Theme Problem

So right now, the default theme is HalloWynn if you're not logged in. So when you do login and use the bar to type your name, the bar changes it's color to black. Thing is, whatever I type is in black too. So whenever I fill in my name - JerrySaDuxlTem - it says incorrect name and I feel like a con artist. Also stay logged in isn't working on my phone ;-;